org.apache.jasper.JasperException: Unable to compile class for JSP:

java jsp tomcat

174,501

Solution 1

This maybe caused by jar conflict. Remove the servlet-api.jar in your servlet/WEB-INF/ directory, %Tomcat home%/lib already have this lib.

Solution 2

The problem is caused because you need to import the pageNumber.Member class in your JSP. Make sure to also include another packages and classes like java.util.List.

<%@ page import="pageNumber.*, java.util.*" %>

Still, you have a major problem by using scriptlets in your JSP. Refer to How to avoid Java Code in JSP-Files? and start practicing EL and JSTL and focusing more on a MVC solution instead.

174,501

Author by

Martin Yang

Updated on December 20, 2021

Comments

Martin Yang over 2 years

Hi I'm trying to compile a simple jsp file with tomcat but I kept having this error message

org.apache.jasper.JasperException: Unable to compile class for JSP: 

An error occurred at line: 13 in the jsp file: /WebContent/test.jsp
Member cannot be resolved to a type
10: <body>
11: <%  
12:     //MyBatisDao myDao = new MyBatisDao();
13:     List<Member> list; // = myDao.func("test");
14:     //out.println("Result list= " + list);
15: %>
16: </body>

test.jsp (at Webcontent)

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ page import="pageNumber.*, java.util.*, java.io.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html> 
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<%  
    List<Member> list;
%>
</body>
</html>

Member.java

package pageNumber;
public class Member {
 private String id;
 private String pw;
 private int point;
 private int lvl;

 public Member() {}
 public Member(String id, String pw, int point, int lvl) {
  this.id = id;
  this.pw = pw;
  this.point = point;
  this.lvl = lvl;
 }

 public String getId() { return id; }
 public void setId(String id) { this.id = id; }
 public String getPw() { return pw; }
 public void setPw(String pw) { this.pw = pw; }
 public int getPoint() { return point; }
 public void setPoint(int point) { this.point = point; }     
 public int getLvl() { return lvl; }
 public void setLvl(int lvl) { this.lvl = lvl; }
 public String toString() {
  return "ID= " + id + ", PW= " + pw + ", POINT= " + point + ", LVL= " + lvl;
 }

}

As far as I can tell, I am having this problem because my tomcat cannot locate the class file, so I have placed my class files at

build/classes/pageNumber (where pageNumber is my package name)
WEB-INF/classes/pageNumber
tomcat\work\Catalina\localhost_\org\apache\jsp\pageNumber

but none of it worked out. Any help?

Edit: After I change my import declaration from

<%@ page import="pageNumber.*, java.util.*, java.io.*" %>

<%@ page import="java.util.List, pageNumber.Member" %>

It actually gave me a new type of error:

org.apache.jasper.JasperException: Unable to compile class for JSP: 

An error occurred at line: 15 in the generated java file
Only a type can be imported. pageNumber.Member resolves to a package

An error occurred at line: 12 in the jsp file: /WebContent/test.jsp
Member cannot be resolved to a type
9: </head>
10: <body>
11: <%  
12:     List<Member> list; // = myDao.func("test");
13: %>
14: </body>
15: </html>